An electric vehicle and a hybrid vehicle are equipped with a motor for running or driving the vehicle, and an inverter that generates AC power for driving the motor. The motor and the inverter are disposed near to each other, electrically connected to each other via, for example, a high voltage cable(s), and together compose a power plant.
Regarding this configuration, Patent Document 1 (Japanese Patent Laid-Open No. 2006-197781) discloses an inverter integrated motor unit that integrates a motor with an inverter, and that includes therein a coolant passage for cooling the motor and the inverter. This coolant passage composes a flow path so as to cool the inverter (an inverter circuit part and a condenser) before cooling the motor, and is configured to supply the inverter, which has an allowable temperature lower than that of the motor, with the coolant having a relatively low temperature.